Latest news with #Orco
Time of India
6 hours ago
- Health
- Time of India
How dengue mosquitoes outsmart even scientists
How dengue mosquitoes outsmart even scientists - their secret hunting techniques revealed Chethan Kumar TNN Updated: Jun 23, 2025, 18:12 IST IST While the dengue mosquito is a smarter predator than previously thought — it can detect you with its legs, too — Indian scientists have detected that a stealthy group of immune cells could be the unsung heroes in fighting the infection It's tough to outsmart a mosquito out for your blood. Here's some consolation. The buzzing insect outsmarts even supersmart scientists. 'Aedes aegypti', the mosquito behind dengue , Zika, and yellow fever , hunts down its prey — humans — primarily by its sense of smell. So, when researchers from the Rockefeller University stripped Aedes aegypti of its primary olfactory gene, Orco — knocking out their sense of smell — they reckoned the female mosquito will lose her hunting instinct. But she was smarter than they were. As a new study published in Science Advances details, when deprived of their olfactory power, Aedes use their ability to sense body heat. Typically, it's the mosquito's antennae that detects odours and heat. But Orco mutants deploy their forelegs to detect human skin temperature.
Economic Times
7 hours ago
- Health
- Economic Times
Dengue mosquito is a much smarter predator than thought, it uses a stealth mode to hunt humans even without smell, study finds
When smell is gone, heat detection kicks in Live Events Indian scientists find new immune cell type in dengue response Immune memory and the vaccine potential The evolutionary advantage of mosquitoes (You can now subscribe to our (You can now subscribe to our Economic Times WhatsApp channel A new study shows that Aedes aegypti , the mosquito responsible for spreading dengue, yellow fever and Zika, can still find human targets even after losing its sense of smell. At the same time, Indian scientists have identified a specific group of immune cells that could reshape the understanding of how the body responds to dengue at Rockefeller University experimented with Aedes aegypti by disabling its primary olfactory gene, Orco, which helps the mosquito detect human odours. They expected this would impair the mosquito's ability to hunt the mosquito adapted. According to the study published in Science Advances, even without its sense of smell, the mosquito could still locate humans by sensing body heat. The researchers discovered that Orco mutants used their forelegs, not just their antennae, to detect skin was linked to a heat-sensitive receptor called Ir140. When Orco was removed, the mosquito compensated by increasing the activity of Ir140, a process known as upregulation. This kind of sensory compensation is common in humans, such as improved hearing among people with visual impairments. The same pattern in mosquitoes points to how evolution has shaped them into efficient it was only when both Orco and Ir140 were knocked out that Aedes aegypti lost its ability to sense human a separate study, Indian scientists at the National Institute of Immunology (NII) and AIIMS Delhi, along with international collaborators, have identified a key group of immune cells that play a central role during dengue immune cells — a subset of CD4+ T cells — are known as PD-1+CXCR5–CD4+ T cells. They activate B cells, which are responsible for producing antibodies. This process is mediated by a signaling molecule called conventional follicular helper T cells that work within germinal centres of lymph nodes, these newly identified peripheral helper cells operate outside them — in extrafollicular niches — and may even reach inflamed discovery provides new insight into why antibodies behave unpredictably in dengue. Antibodies can protect the body, but in some cases, especially among individuals with past dengue infections, they can worsen the disease through a process known as antibody-dependent enhancement (ADE).The study also found that PD-1+ helper T cells are not uniform. They divide into IL-21-producing helper cells and cytotoxic cells. Some may remain in the body as memory cells, possibly contributing to long-term immune are still trying to determine whether these cells offer protection or increase risk during future dengue infections. If understood better, these cells could help develop targeted vaccines against advancements in science, the mosquito remains one step ahead. Swarnadip Ghosh, a researcher from the National Centre for Biological Sciences (NCBS) in Bengaluru, described the mosquito's ability in verse:'When scent fades out,the mozzie's not beat,She hunts you down bythe stink of your nose? No problem —she's got legs that feel heat,And still thinks yourblood is a five-star treat.'(The article was orignially published in TOI)
Time of India
8 hours ago
- Health
- Time of India
Dengue mosquito is a much smarter predator than thought, it uses a stealth mode to hunt humans even without smell, study finds
A new study shows that Aedes aegypti , the mosquito responsible for spreading dengue, yellow fever and Zika, can still find human targets even after losing its sense of smell. At the same time, Indian scientists have identified a specific group of immune cells that could reshape the understanding of how the body responds to dengue infection. When smell is gone, heat detection kicks in Researchers at Rockefeller University experimented with Aedes aegypti by disabling its primary olfactory gene, Orco, which helps the mosquito detect human odours. They expected this would impair the mosquito's ability to hunt humans. Instead, the mosquito adapted. According to the study published in Science Advances, even without its sense of smell, the mosquito could still locate humans by sensing body heat. The researchers discovered that Orco mutants used their forelegs, not just their antennae, to detect skin temperature. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like Buy Brass Idols - Handmade Brass Statues for Home & Gifting Luxeartisanship Buy Now Undo This was linked to a heat-sensitive receptor called Ir140. When Orco was removed, the mosquito compensated by increasing the activity of Ir140, a process known as upregulation. This kind of sensory compensation is common in humans, such as improved hearing among people with visual impairments. The same pattern in mosquitoes points to how evolution has shaped them into efficient hunters. However, it was only when both Orco and Ir140 were knocked out that Aedes aegypti lost its ability to sense human heat. Live Events Indian scientists find new immune cell type in dengue response In a separate study, Indian scientists at the National Institute of Immunology (NII) and AIIMS Delhi, along with international collaborators, have identified a key group of immune cells that play a central role during dengue infection. These immune cells — a subset of CD4+ T cells — are known as PD-1+CXCR5–CD4+ T cells. They activate B cells, which are responsible for producing antibodies. This process is mediated by a signaling molecule called IL-21. Unlike conventional follicular helper T cells that work within germinal centres of lymph nodes, these newly identified peripheral helper cells operate outside them — in extrafollicular niches — and may even reach inflamed tissues. This discovery provides new insight into why antibodies behave unpredictably in dengue. Antibodies can protect the body, but in some cases, especially among individuals with past dengue infections, they can worsen the disease through a process known as antibody-dependent enhancement (ADE). Immune memory and the vaccine potential The study also found that PD-1+ helper T cells are not uniform. They divide into IL-21-producing helper cells and cytotoxic cells. Some may remain in the body as memory cells, possibly contributing to long-term immune response. Researchers are still trying to determine whether these cells offer protection or increase risk during future dengue infections. If understood better, these cells could help develop targeted vaccines against dengue. The evolutionary advantage of mosquitoes Despite advancements in science, the mosquito remains one step ahead. Swarnadip Ghosh, a researcher from the National Centre for Biological Sciences (NCBS) in Bengaluru, described the mosquito's ability in verse: 'When scent fades out, the mozzie's not beat, She hunts you down by the stink of your feet. No nose? No problem — she's got legs that feel heat, And still thinks your blood is a five-star treat.' (The article was orignially published in TOI)
